I have ran into a situation where I have made an accessory that should also animated the avatar, but then I have created an "accessory" that's actually based on empty clothing instead. If I added the animation to an empty accessory, the avatar would not have been animated.

Though if the accessory reacts to multiple bones in IMVU avatar, then it should be based on empty clothing with some elusive body part ID, that's a no brainer. But my accessory was only attached to one hand bone.

And I missing something? Is there a way to animate the avatar with an actual accessory (with a unique skeleton of it's own) or not?

I came around the same issue quite some time ago.. i wanted to make a fish slap product that including the slapping action of the avatar combined with a slight wave deformation of the fish mesh itself. I remember i was able to do it by making a xpf morph of the accessory mesh that triggered at the same time as the avatar action. Leave you a link to the product so you can see what i did there cos i dont remember exactly, lolol. Its been quite a while XD